Apparatus for and method of making thin metal containers



J. H. FRIDEN APPARATUS FOR AND METHOD OF MAKING THIN METAL CONTAINERSJune 20, 1939.

Original Filed Nov. 20, 1936 3 Sheets-Sheet 1 Zinbentor June 20, 1939.

J. H. FRIDEN I 2,162,776

APPARATUS FOR AND METHOD OF MAKING THIN METAL CONTAINERS Original FiledNov. 20. 1936 3 Sheets-Sheet 2 A Smmutor June 20, 1939. J. H. FRlDEN 32,162,776

APPAR Tus FOR AND METHbD OF MAKING THIN METAL CONTAINERS Original FiledNov. 20, 1936 3 Sheets-Sheet 3 Patented June 20, 1939 APPARATUS FOR THINMETAL John B. Frldn, Maplewood, N. 1., ,assignor to The Snn'lnbeCorporation; Hillside, N. J., a corporation of New Jersey I Originalapplication November- 20, 1936, Serial No. 111,788. Divided and thisapplication November 9, 1937, Serial No. 173,634

9 Claims; 7 (c1. ant- 1o This invention relates to apparatus for amethod of producing thin walledmetal icontainers of the collapsibletypeintehdedlforsim' gle-use purposes. Ithas particular reference to 5; theproductionoi containers of the sort men tioned, adapted to retain liquids or other fluid substances which arejto be completely dispensed andused when the container'is first opened.

A particular object of' the invention has to provide for' quickly andeconomically producing in large quantities containers of the charactermentioned having integral closures that can be readily opened withoutthe use of implements, are completely air-tight and liquid-tight,

iii: are sufliciently sturdy to prevent accidental opening, and, whenintentionally opened-,1provide a relatively large passage for thedischarge of their contents. r

For further details as to the features and advantages of the containerwhich the present fimproved method and apparatus are especially adaptedto produce, reference may be had to the copending application S. N.111,788, filed on November 20, .1936, Patent 2,112,085, issued March221938, of which this applicationis .a

division.

In the production of the container it has been.

an object. to so simplify theo'perations-that the containermay bemanufactured in large quasi-- tities at low cost. Toward thisenddteislargely produced by a single extrusion operation followed by a minimumof finishing operations. This phase of the invention embraces not onlyimjproved methods but also novel relationships between the parts oftheapparatus for producing the container. 1

These and other objects and advantages of cordance with the invention.

trusion press constructed and employed in Referring-now tothe-drawing's,the improved container, which the present method and apparatus areparticularly designed to 'produceis preferably formed with a cylindricalside wall I.

and a shoulder H provlded at one end to'par tlally close the: tube. Theshoulder ii is, in-

clined slightly to a true transaxial plane.

inclination of this shoulder need not be, and preferably is not, asgreat as in the usual col- .lapsible tube construction ;for'the'packaging of tooth paste and the-like; it may suitably be an angle of,say IO-to 15tothetransa xial plane,

or, even less. If desired, it might even be substantiallyperpendicular-to the axis of the container. At the center of theshoulder I I there is provided a readily removable closure in the formof a fiat disc l2, which is joined integrally with the metal of theshoulder by a thin, short, annular neck l3. 3

This container lends'itself'readily to production by an extrusionoperation which is capable of forming the shoulder ll, end closure i2,and neck portion it in a smooth, completely finished state within lessthan asecondp The opposite or'open end of the tube ill will terminate inan the invention will become more apparent from the detailed descriptionof an illustrative form of the samewhich will-no w beigiven inconjunction with the accompanying drawings in which: Figure 1 is aperspective view of the improved container. l 0 Figure 2 is a verticalsection through the axis of the container.

Figures 3, 4 and 5 areview's partly in section and partly in elevation,showing the relation be-- tween the punch and die at'diiierent stages ino the operation ofthe press. p

Figured is a detail showing certain pin controlling camsand is takenalong, the lined-4 of Figure 7, and v Figure 7 'isa view, partlyjinvertical section 5 and partly in elevation,- of portions of an exany.printed matter irregular edge It upon completion of the extru-. sionoperation and, therefore, informing the fill-.- ish'ed container asmall' section or annular band IQ will be removed, and the tubethustrimmed to length, by a. simple cutting tool, of a type well knownin the art. In using the new container,

the liquid or other contents will be introduced through the open endleft upon the removal of the ring 15 and this end may then be sealed inany convenient way, as by simply folding and crimping the edges togetherin a. manner well known in'connection with ot er forms of -collaps'ibletubes. Any suitable a gn, such as designated il in Figure '1, may beappropriately applied to the surface of the wall It. This may include abase coating of any selected color and which-it may be desired to add:tothe tube for advertising purposes and by way of instructions. Methodswell known in the .art,may be employed for the coating and printingoperationa If the tube is to be used. for the packaging of llqi ors .orother potable or edible products, it is preferably formed ofsubstantially pure tin.

However, the container, maybe made of other readily eiftrudable metalsor combinations or al- I loys ofmetals suitable for use in connectionwith the particular substance to be packaged. v

While I do not desire to be limited to any specific dimensions or wallthicknesses of the'various portions of the container, a form which hasbeen found most excellent for the packaging of a siiitable quantity ofliquor to constitute one drink is a tube havinga diameterof 1 inch anda,wa1l thick.- ness of about .003 of-an inch. The package when filledhas an overall length of about 4 inches.

. Shoulder II'- should preferably be considerably thicker than the wallID was to provideja desired rigidity. It may well be about '.025 of aninch thick. End closure I2 is preferably of even greater thickness andmay, for example, .be about .050 of an inch thick. The neck portion l3,however, should be extremely thin, i. e., say between .001 and .002 ofan inch and preferably not more than about .0015 of an inch in wallthiclmess, in

orderthat it may be readily pierced by the thunfbnail for theremoval ofthe closure l2. It need the as short as possible so as to avoid undulyweakening the container. It might be made as long as -.10 of an inch butdue to difliculties of'manufacture, it is very desirable to limit thelength of the neck [3 to only suflicient to allow insertion of thethumb-riaih While the diameter of the'closurel2 may be varied to suitparticular requirements, depending upon the fluidity of the contents andthe speed with which it is desired to discharge the contents, it hasbeen found that a closure of about of 'an inch in diameter is ideallysuited for a package intended to contain liquor; If it is desired todischarge the contents more slowly and, for example, require eithersqueezing or shaking of the tube to accomplish it, the closure may bemade quite small, say .10 of an inch in diameter. A package of thecharacter specified, having the dimensions indicated, will retain aboutof a* pint of liquid. Obviously, the size of the container and thedimensionspf various portions of the container may be varied withinrelatively wide limits without departing from the general prin-:

ciples and scope of the invention. However, the

thickness and length of. the neck portion I3 is of considerableimportance and should not be varied materially without regard to theconsiderations mentioned.

-Various manufacturing difficulties have been encountered in theproduction of the improved container. As previously stated, thecontainer is primarily formed by an? extrusion operation 111- volvingthe use of a punch l8 and a die". .These may suitably be embodied in anextrusion press of appropriate character, such as the one disclosedin-my prior Patent No. 2,023,879, granted December '10, 1935. Referencemay be had to that patent for details of construction. Only-those por--tions having a direct bearing upon the present invention are shownherein. The die isprovfded with a recess 20-, which is of slightlygreater diamv eter than that of the lower extremity of the punch.

This, as is understood in the art, is slightly larger than the mainshank of the punch, by. either providing a head or a slight outwardtaper at the lower end of the punch. The distance between 1 the corner2| orpoint of largest diameter-of the tube. This thickness may be veryaccurately determined and maintained. It should be pointed out, however,that it is not possible to confine accurately within very definitelimits the ,thickness of any, wall that is disposed substantiallytransversely to the direction of movement of the punch. Such a wall mayvary as much as .020 of an inch in thickness in the extrusion of a largequantity of tubes. This is due in part to the effect of a variation intemperature and in part to variations in the metallurgical structure ofthe slugs perature will bring about variations in the length of thepunch and these will result in-corresponding differences in thethicknesses of transversely disposed walls. The ease or difliculty withwhich slugs may be extruded is afiectednot only by tem-- perature but toan even greater extent by variations in the grain and hardness of theslugs. It has been found that slugs ofidentically the same compositionmay vary widely in their hardness and extrudability. When a relativelyhard slug is encountered, the parts of the press structure will yield'orspring to a greater extent, than when an easily extrudable slug is used,and hence the punch will not descend as far into the die.

For the production of the improved container the punch is provided witha projection 22 extending beyond a shoulder 28 at the lower end of thepunch. The projection is of the appropriate. length and diameter to formthe end closure l2 and neck ll of the tube while the shoulder 23 is ofthe appropriate form to produce the shoulder l l of the tube incooperation with a slightly tapered bottom portion 24 of the die recess.The projection 22 of the punch maysuitably be formed sepabeing extruded.Relatively small changes in temrate from the main shank of the punch ona small position.

The die has extending through it, from the center of'the bottom of therecess to the bottom of the die, an opening or passage 25, which is ofonly slightly greater diameter than the projection 22 The diflerencebetween the diameter of the passage 25 and that of the projection 22will determine the 'wall thickness of the neck portion i3 of the tube.For the production of the typical tube described, therefore, thisdiflerence should be ..003 of an inch. Within the passage 25 is aslidable pin 26 forming a movable section of the die bottom. This pin isadapted to shift in the course of an extrusion operation and for thispurpose may be controlled by suitable cams as well as by a spring,desired, in the manner explained in my prior Patent No. 2,023,879. Theconnections for accomplishing this control are fully, set forth in thatpatent and will, therefore,

beonly briefly described here. They include a rod formed in severalsections, .21, 28 and 29, the

latter two of which pass through an adjustabl sleeve 30. The'lower endof section 28 is adjustably connected with one end of a lever 3| mountedon theframe and having its other end connected with the lower endofa-vertically extending rod 32. This rod is surrounded by a spring 33which; normally urges it downwardly. At its upper endthe rod isconnected withan arm 35 secured to a pin 38 having also secured-thereto.a painof roller-carrying arms 30 and 31 whose rollers engage cams 38and 39, respectively. These cams are secured to alshaft 4.0, which is amain drive shaft for the press and serves to operate the punchin themanner explained in said prior 6 I A...

Now, while the devices for controlling the p 26 are similar to thosedisclosed in my prior patent, nevertheless, for thepurposeof'successfully forming a container of the-type constituting a '10 partof the present invention, it is necessary to time the operation of thecams, which control the pin 26, somewhat differently from the timingexplained in my prior patent. 'In the operation of the machine toproduce 'the improved con- 15 tainer, the cams 38 and 39 for controllingthe pin 26 are so-cons'tructed and arranged that when the punch firstengages the upper surface of the slug, thetopof the pin 26 will be held'either substantially flush with (the innermost edge of the die surface24 or will be elevated slightly above this to engage the under surfaceof the slugl' If it is held in the'first position mentioned, thesubsequent downward movement of the punch will first bend the slugslightly to conform-with the concavity of the die bottom. The projection22 will then penetrate the material of the slug and sijue'eze the metalaside until the section between the bottom ofthe projection'22 and thetopof the pin 26 is substantially equal in thickness to the desiredthickness of the closure 12. Should the top.'of the pin 26 be initiallyelevated into engagement with the bottom of the slug, it will be apermitted to drop under the pressure of the projection 22, exertedthrough the slug, until it is 35 substantially flush with the innermostedge of the surface 24. From this point the operation is the same asbefore, i. e., the .metal issqueezed with the pin held in this positionuntil the closure portion l2 of the tube is produced in substantially.its final form; A part of thissqueezi'ng may take place simultaneouslywith the depression of the pin in this mode of operation. In the courseof accomplishing this formation of the closure portion I2, the shoulder23 will 'have commenced the squeezing of the rest of the slug to startthe metal upwardly along the punch in the manner indicated in Figure 4.

\ Now, after the "slug has been reduced to the desired thickness betweenthe end of projection 22 and the top of pin 26, the cams will permit thepin 26 to descend in unison with the further movement of the punch. Thetotal amount of downward movement of the pin below the inner edge ofshoulder is relatively small, being only length (if the neck l3. Duringthis downward movement ofthe pin the metal to form the neck' l3may'be'supplied in several ways. It may be partly supplied by thedownward extrusion of some of the metal being squeezed between theshoulders. and 24, although due to the exces- -siv'e resistance toextrusion throughsuch a small passage it-is questionable whether much,if any, i of the metal is supplied in this way. Itis probeably suppliedprincipally, ifnot entirely, by the drawing or nee action produced bythedownward movement of the closure portion I! of the tube in advance of.the projection 22. Ifdesii'ed, the downward movement of the pin 26 maytake ward movement of the punch, or the downward movement of the pin maybe arrested a trifle before the downward movement of the punch so thataslight, additional squeezing action takes place between the bottom ofthe punchfand' the trolling linkage. Should this spring be provided,

equal to the thickness of the closure 12 andthe.

place at a slightly slower rate than the down-' top of the pin. This,then, will provide a slight upward extrusion of a portion of the metalbe-' tween these surfaces. v e 1 However, here again the resistance toextrusion through the slender. passage is so great that 5 it is not,desirable'to attempt to extrude any substantial quantity of metal inthisway. My experiments have shown that it is not possible to completelyform the neck" by the upward extrusion of metal squeezed from betweenthe b0ttom of the projection 22 and the bottom of a solid die or.the topof a pin. that .is held stationary. The pressure required to extrudemetal through such a narrow passage as to produce a neck having a wallthickness of about .0015 of an inch is 15 so great that either the punchor the die, or both, would break before a suflicient portion of theincompressible metal could be displaced through this passage. It is forthis'reason that it is important to reduce the metal between the bottombecome excessive if a slight outward taper to the passage is notprovided. Accordingly, I form the, recess 20 with a very slightoutwarditaper from bottom to top and 'I form the punch shoulder 23 at aslightly'greater angle to the transaxial plane than the shoulder 24. Thenecessity for this illustrates the 'difliculty, or evenimpossibility,-of extruding from a relatively large passage such as thatbetween projection 22 and pin 28, into the very thin passage betweenprojection 22 and die 40 opening 25. J 'I'he control of the pin 26 may,if desired, be entirely through the cams 20 and 39, although the spring33 is preferably included in the coriit will be understood that thepin28 will be positively held by the cams. at a point with its top flushwith the inner edge ofa shoulder 24 until the metal attains the properthickness between this pin and projection 22. A drop may then be aprovided on the cam to allow the pin '26 to be forced downwardly againstthe): action of the spring until the pin isdepress'ed to the extentrequired to form a neck I 3 ot ithejdesired length. 5

At this point further downward movement of the pin may be arrested bythe coaction of positive stops, as explained in my prion patent, but atthis time the downward movement of the pimch should also besubstantially completed. Dueto so the precise lower limit of the punch,as has been explained, it is preferable to so adjust'the positive stopsthat they are engaged only when the punch'travels to substantially itsextreme lowerlimit for any particular set up of the mechanism.

As alsoexplained in myprior patent, the upward movement of the pin 28should be delayed until the punch his been partially retracted so that aslight slippa e is? produced between the the punch. Thisallows for theeasy removai of .the tube by the air hlast'means at the'appropriatetime.

n connection with the fdi'maflon or the neck 15 n, it should be observedthat thereis a fairly definite limit to the length of neck that can be'produced, As stated before, anattempt to ex-- trude much metal throughsuch a narrow passage as is provided between the projection 22 and thepassage 25 will result in the breakage of the punch or die, or both.Moreover, an attempt to lengthen the neck by a drawing or neckingoporation is apt to result in the fracture of the neck It) at somepoint, thus rendering the tube defective.

My experiments indicate that the maximum operation is completed.

2. A method of producing from a disc-like sluglength towhich the neck l3may be safely extended when its thickness is not more than" .0015 of aninchis %of an inch. I

While a preferred method of and apparatus for producing a'special typeof container have 7 been disclosed in considerable detail, it will beunderstood that various changes may be made in both the-apparatus andthe process without departing from the general'principles and scope ofthe invention. The terms and expressions.

used herein have been used as terms of description and not oflimitation.

What I claim is:

A 1. A method of producing a thin, metal, tubular, collapsible containerwhich comprises forcing a punch against a slug in a die recess andcommencing the upward extrusion of the tubular container while theentire die "bottom remains stationary until a portionof the slugattains'substantialiy the thickness desired for a corresponding portionof the container-and then permitting a corresponding portion of the diebottom to recede in unison with the punch the extrusion a thin, metal,tubular, collapsible container having an integral; readilyremovableclosure which comprises forming the closure of the desired finalthickness substantially within the body of the slug while simultaneouslyextruding a portion 01 a thin, metal, tubular, collapsible containerhaving an integral, readily removable closure which comprises formingthe closure of the desired final thlcknes while simultaneously extrudinga por- ;tioh of the tubular side wall, and then forming a' thin neckbetween the under surface of the slug i eratlon.

4. A method of producing from a disc-like and the closure at least inpart by a drawing opslug a'thin, metal, tubular, collapsible containerhaving an integral, readily removable closure which comprises formingthe'closure ofthe desired final thickness substantially within the bodyof the slug while simultaneously extruding aportion of the tubular sidewall, and then forming a'thin neck between the bottom, of the sing andthe closure by advancing the closure with the end of the punch'wlthoutsubstantially modi.-'

the tubular side wall, and then drawing said closure away from thetubular body torfor'm a neck between them having a wall thickness ofless than an extrudable dimension for the metal of said slug as it isbeing operated upon.

f .6. A method of producing a. thin, metal, tubular, collapsiblecontainer, having an integral, readily removable closure ,whichcomprises forcing a punch against a slugof extrudable metal in adierecess to form said closureof substantially.

its final thickness, and then forcing said closure away from the balanceof said slugto form a neck between them having a wall thickness oflesssaid slug. as it is being operated upon;

, 7. A method of producing a thin metal, tubular, collapsible containerhaving an integral, readily removable closure which comprises forcing apunch against a slug of extrudable metal in a die recess to form saidclosure of substantially its final thickness,and then "forcing saidclosure away from the balance of said slug to form a neck between them'having a wall thickness of less than 'an extrudable dimension forthemetal of said slug as it is being operated upon while simultaneouslyextruding the metal along said punch toformrthe main tubular body.

a. A method of producing a thin, metal, tubular,;.collapsib1e containerhaving an integral, readily removable closurewhlch comprises forcing apunch agalnst a slugof extrudable metal in a die recess while the entirebottom of said slug is supported to form said closure of substantialLvits final thickness, and then forcing said' closure away from thebalanceof saidslug to form a neck betweeen them by causing a portion ofthe die bottom coincidingwith said closure to recede in advance of thepimch at the same rate as the latter. V I

9. In apparatus of the class described a die having a recess,- a punchadapted toenter said recess, said die "having a passage therethrmlghsired thinness and then to provide for movement of said punch and pin inunison.

JOHN H .'FRJDEN. V

than an extrudable dimension for the metal of

